Antenna construction



P 2, 1952 D. P. WORDEN 2,609,502

' ANTENNA CONSTRUCTION Filed Feb. 15, 1949 if I Patented Sept. 2, 1952ANTENNA CONSTRUCTION Donald P. Worden, Rochester, N. Y., assignor toGeneral Motors'Corporation, Detroit, Mich., a

corporation of Delaware Application February 15, 1949, Serial No. 76,614

3 Claims.

This invention relates to radio antenna means I and more particularly toradio antennae adapted to be used on vehicles and of the telescopic orcollapsible type.

Telescopic antenna means for automobile use has become quite universaldue to the need for length during receiving of signals but a, retractionto the approximate size of car outline when entering an enclosure suchas a garage.

It is an object of my invention to provide an improved form ofcollapsible antenna for radio reception on vehicles.

It is a further object of my invention to provide an improved electricalcontactor construction for antennae of the telescopic type.

With the above and other objects in view which will become apparent asthe specification proceeds, my invention will be best understood byreference to the following specification and claims and theillustrations in the accompanying drawings, in which:

Fig. 1 is a vertical sectional view through a multi-section telescopicantenna embodying my invention; and,

Figs. 2, 3 and 4 are each an enlarged sectional view taken respectivelyon the lines 22, 3-3 and 4--4 of Fig. 1.

Referring now more specifically to the drawings, there is shown in Fig.l a portionof a car 2 which may be the cowl or fender or any other parton which it is desired to mount the antenna. Through any insulatingmember 4 the lower section 6 of an antenna assembly is rigidly securedto the car part 2 by any conventional means. This lower section 6 isformed of a hollow tube of proper diameter to accommodate the other andsmaller telescopic sections within it when they are in the retracted orcollapsed position. The member or section 6 is of the same diameterthroughout its entire length except for a section 8 adjacent to butspaced from its upper end where it is necked down for a short distanceto a smaller diameter and the upper end I is flanged inwardly at [2 tomaintain packing material M in the upper end which may be felt or somesimilar material.

The next smaller section l6 has an outside diameter equal to the insidediameter of the reduced portion 8 of the tube 6 and this portiontherefore acts as a bearing or gland for support. It is of the sameconfiguration as the section 6 except that the lower end has an expandedrib is thereon which prevents this section from being withdrawn from thelower one. This section I6 likewise has the reduced portion 20 and theupper end section 22 with packing material 24. As many sections may, ofcourse, be provided. as are necessary to give the, desired final lengthof antenna.

The last or uppermost section 26 is a hollow rod provided with a ballcap 28 to seal the upper end and having a portion adjacent its lower endexpanded to form a ring 30 to prevent its withdrawal from the next lowerand larger section.

Provision must be made for good electrical connection between theseparate sections of the antenna and this is provided by wire brushassemblies 32 carried in the lower ends of each of the smaller tubes andbearing against the inside surfaces of the next larger section intowhich it telescopes. These wire brush assemblies are formed of a plug 34which is driven into the end of the smaller section and which has driveninto one end thereof a rod 36. To this rod are secured a plurality ofconducting wires 38 in radial relation and having considerablelongitudinal rigidity to form in effect a brush, said radially extendingwires being rigidly secured to the central rod support by an axiallyextending wire 40 wound around groups of the radially extending brushwires. A flat head 42 on the rod 36 prevents the group from slipping ofithe outer end. The securing wire 40 may be soldered or otherwisefastened in place and its inner end staked into the plug 34. The size ofthe plug 34 and the diameter of the brushes formed by wires 38 will bedifferent for each connection, of course. The ends of the wires willscrape over the whole inner surface of the adjoining section andmaintain good contact therewith in any position and current may easilyflow from one section to another. They also serve as a spacing supportfor the inner section end.

The packing material l4 or 24 will help to seal the joint betweensections and prevent moisture and dirt from getting into the interior ofthe device. The reduced sections 8 and 20 as well as providing anabutment for the packing at the ends of the sections also provide fingerholds by which to grasp the sections to pull them out or force them backin as in general the outer surface of the tubes is smooth and diiiicultto hold.

I claim:

1. An extensible radio antenna comprising an outer metal sleeve havingmounting means at one end, packing means at the other end and anintermediate portion of reduced cross section, an inner metal sleeveslidably mounted within the outer sleeve and having a. portion fittingsnugly within the reduced intermediate portion or the outer sleeve andwithin said packing means, means for preventing longitudinal separationof said members, and a plurality of stifi metal brush membersmechanically and electrically connected to the inner end of said innersleeve and diametrally disposed within said outer sleeve and "bearingagainst the inner surface of said outer sleeve substantially completelytherearound, to provide and maintain effective electrical contactbetween said sleeves.

2. An extensible radio antenna comprising an outer metal sleeve havingmounting means at one end, and an intermediate portion of "reduced crosssection, an inner metal sleeve slidably mounted within the outer sleeveand having a portion fiitting snugly within the reducedfintermediateportion of the outer sleeve, means for 3. An extensible radio antennacomprising an outer metal sleeve having mounting means at one end, and aportion of reduced cross section, an inner metal sleeve slidably mountedwithin the outer sleeve and having a portion fitting snugly within thereduced portion of the outer sleeve, means for preventing longitudinalseparation of said members, and a plurality of stiff metal brush membersmechanically and electrically connected to the inner end of said innersleeve and diametrally disposed within said outer sleeve and preventinglongitudinal separation of said memhearing against the inner surface ofsaid outer sleeve substantially completely therearound, to

vprovide and maintain effective electrical conltactbetween said sleeves.

DONALD P. WORDEN.

REFERENCES CITED The following references are of record in the file ofthis patent: a a a 7' UNITED STATES .PATEN'I'S

